Heat exchangers commonly have a plurality of parallel flat sided extruded or roll formed tubes connected at opposite ends to a pair of header-tank assemblies, and a plurality of fins between and bonded to the tubes to facilitate efficient heat transfer to the surrounding area. Each header-tank assembly generally comprises a header with slots therethrough for receiving the tubes, and a tank secured to the header to contain a heat exchange fluid medium and receive the same from the tubes. The fins are brazed or soldered to the sides of adjacent tubes, and the tubes are brazed or otherwise bonded to the header along with the tank to assure leak free joints.
During assembly, the header and tank must be secured to one another to seal the joint therebetween. Tabs of various sorts are known for tank retention of headers. For example, T-shaped tabs located on the header are employed in Buchanan U.S. Pat. No. 5,195,579. In this patent, the so-called bars or tops of the T-shaped tabs are bent inwardly in their entirety over a flange on the tank so as to hold the header and tank assembly together. While such known connections between the tank and the header may perform acceptably for their intended purpose, there is always room for improvement. For example, there is a continuing desire to make the connection easier to form and to improve pressure resistance. In addition, there is a need for an improved means of attaching side pieces to the headers.